Baking oven



May 18; 1937-, l.. D. HoULls 2,080,719 I BAKING OVEN Filed April l0, 1934 3 Sheets-Sheet 1 /1/1//1//1//11/1. f N 'n /l n Summa L. D. HULIS BAKING OVEN May 18, 1937.

v Filed April 10, 1934 5 Sheets-SheetI 2 glulwm|wr Nm.

May 18, 1937. L, D. HouLls 2,080,719

BAKING OVEN Filed April lO, 1954 -3 Sheets-Shea?l 5 Patented May 18, 1937 UNITED STATES PATENT OFFICE BAKING OVEN Louis D. Houlis, Dallas, Tex. Application A'pril 10, 1934, Serial No. 719,833

Claims.

This invention relates to new and useful improvements in baking ovens. j One object of the invention is to\provide an improved oven wall construction, whereby the Il heat is evenly distributed within the oven, but is kept from excessively radiating through the wall and dissipating over the outer surface.

Another object of the invention is to provide an improved heating and Ventilating system and so arranged that when the temperature drops below a predetermined' degree a maximum amount of fuel is supplied to the burners and at the same time ventilation is automatically controlled. Also whereby when the desired temperature is reached, bothy the fuel supply and the' vide means whereby the heat and ventilation are proportionately controlled and cold air currents are prevented from circulating in the baking chamber and waste heat is also obviated.

A construction designed to carry out the invention will be hereinafter described, together with other features of the invention. 0 j 'The invention will be more readily understood from a reading of the following specification and by reference 4to the accompanying drawings, in which an example ofthe invention is shown, and wherein:

Figure 1 is a perspective view of an oven constructed in accordance with the invention,

Figure 2 is a horizontal cross-sectional view of the oven\,\por tions of the oven floor being omitted to show underlying pipes,

Figure 3 is a transverse vertical sectional view of the oven,

Figure 4 is a detail of the corner construction,

Figure 5 is a sectional detail of the wall,

Figures 6 and 7 are details of the operating connections for the front damper, 7

Figure 8 is a horizontal cross-sectional view of the door structure,

Figure 9 is a vertical sectional view taken on the line '9 9 of Figure 8,

Flglie l0 is a partial elevation of the door mecha. sm, and

Figur 1l is a detached view of the thermostatically controlled fuel valve. l

In the drawings the numeral IIl designates the front wall, II the back wall, I2 the end walls,

,I3 the top or roof, and I4 the floor of the oven.

The oven is given a general rectangular shape which lends to the structural details thereof.

Each wall Ill, I I, I2 and -I3 is substantially the same and a description of one will explain all.

In building the wall an inner frame I5 and an outer frame I6 are constructed. 'Ihese frames are formed of angle bars and are rectangular in shape. Each frame is provided with uprights I'I, preferably made of angle bars. The frames are spaced apart with their flanges directed inwardly so that the flat sides of the bars face outwardly. Connector straps I8 extend between the frames at intervals and constitute the only connections therebetween. It is preferable to weld frame bars, uprights and straps in place, thus avoiding rivets or bolts and making a more substantial construction.

Each wall has-an outer covering or shell formed of one or more metal sheets I9 welded or otherwise secured to the outer flat faces of the frame I6 and uprights; while one or Vmore sheets 20 are Awelded or otherwise fastened to the outer flat faces of the frame I5 and uprights, to form the lining of the oven. The inner lsheets 20 may be ma'de of any desirable sheet metal, such as copper alloy steel; while the outer sheets I9 may be of heavlervrust resisting metal. Suitable insulating material, ksuch as mineral wool 2|, is

packed in the walls between the shell and the lining and this has been omitted from the drawings, except at portions in order to better illustrate the structure. Retainer strips 22 are placed in the frames at their bottoms to support and retain the insulating material.

In setting up the oven the inner frames I5 are bolted together, as is shown at 23 in Figures 2 and 5, along the upright corners. In order to seal the baking chamber the inner sheetsy 20 of one wall may be bent around the frame so as to lie flat against the marginal portions of the lining of the other frame, as is shown in Figure 5.

formed are also filled' with insulating material.

The chamber formed by the walls which have been described is -supported in a base which is formed by sills 29 `disposed under the end walls I2 connected by angle bars 30 extending under the front and back walls. The battens 25 may be extended down to cover the corners of the base. The o rv I4 is supported on a pair of angle bars 3| xtending between the sills at the center provided with slots 34. A sliding door135 upright T-shaped rails 36 engaging in the slots,

as is shown in Figures 8 and 10. The door 35 `is considerably narrower than the front willi Il (Figures 3, 8 and 9) and has= its inner .surface substantially ilush with the lining 2li.` 'I'he has a pocket or recess 31 for receiving thef'door 35 when the latter is lslid downwardly ,to open it. 'I'he rails 36 depend from the door and chains 38 are fastened thereto. These chains pass over sprockets 39 and carry counterbalancing weights I 40, whereby the door is held in 'the position t'o which it is moved, openor closed. v The sprockets 39 are fastened on a shaft 4l extending through the end walls I2. Hand wheels 42 are' fastened on the ends of thevshai't,` whereby lthe shaft may rotated from .either end of the oven to `open orclose the door... i

. A revolving reel 43 is` journaled in the oven'l A not nue or manifold- 'u is formed longitudinally in thecentral vportion of; the top I3. lThe manifold has a vent 45'. '1A rear arch lsheet 45,. curves downwardly from the rear portiori of 'the' manifold to the iop ofthe upnghtiiue nniounted on'the reary wa1l. 4This fl'ue terminates' short of the bottom I4 its is" to carry o!! excess heat; A front archk sheet 48, curves downwardlyffrom vthe fron't portion-'of themanifold 44 towardthe front wall `Il and has its lower willbe conducted tothe manifold. This damper` end spaced fromthe lining 2l by a bracket 4l just'above the door frame132. These arch-sheets '.obviate corner pockets in the top of the .baking v chamber andproperly deflect the heat currents onto the reel. Above'the rear arch 45a damper is hinged in the bottom of the manifold so that air currents passing up 'the iiue 41 vmay be di`s` charged into' the manifold' when the damperis opened. This damper ismounted on a Vshaft `Slfand ishinged'inthe end walls I2.

A similar front damper 52 is mounted in the bottom of the manifold overhangingthe arch sheet 45. When this damper is opened air currents and fumes .passing through the'bracket 45 is mounted on a shaft 53 journaled in the `end walls I2. This providesfor ventilationgwlien-l the doorv is opened so as to carry oif the fumes and hot air currents instead of permitting th to flow-into the room.

In th'e bottom of the ovenl provide burners tion thereof. Alhese burners may be of any suitable structure andare employed for producing o a heat. A longitudinal burner 55 is disposed between the burners 54 and is oi' the nnely perforated type for producing ininimum heat. y Fuel pipes 56 mounted under the oor I4 extend inwardly from the front of 'the'oven and are-connected with the burners 54 through said oor. These pipes have the -usual 'mixin heads 51 on their front ends. The burners 54 are arranged in pairs and. the heads if-each pairar'e vconnected by a cross pipe 5l. A manifold. pipe 55 is mounted longitudinally below the pipes 55 and is connected at its ends with laterals 54, which in turn are connected with the pipes 58. On each side of the lateral connection hand valves Il are jgonnected in the pipes 53, whereby the suptrolled. I

A fuel pipe 52 extends under the floor I4 and `is connected through the same with the burner 55.. .This pipe has'a mixing head 53 on its front end similar to the heads 51. A branch pipe 54 extending from the head 63 is connected to a manifold pipe ,65, which is attached at one end to across connection 65 in the manifold 55 as is showninfFigure 2. A gas supply pipe 61 ex- The pipe 65 has a hand valve 85 yfor controlling the supply of gas coming thru pipe Il to the connection y and a'hand valver 10' beyond the connection withV thepipe 54. A flexible hose 1I is connectedto the pipe-65 and Acarries a long noav12. A swinging door 13 is mounted at the center and bottom of th'evi'ront wall I5. By

rswinging'this door outwardly', thev nozzle maybe inserted' -into'the baking Vchamber to light the` burners'.l When'the nozzle is not inuse the-valve *'15 is closed.- l It: 'is obvious' that by-operating the handfvaives' the supply: ofgas to the'vbllrners may be controlled. 'WA fuel 'supply pipe 141 is connected with, the

pipey B1. as :is showninFigux-e .1. yAn electrically operated valve 15, of \the type now commonly. inl

f isvconnectedin thel pipe '.14 andthe-minimum gas pipe 55 is l.connected in the pipe v14 ahead of said valve so. that gas .is ,constantly suppliedto said pipe 68. The-valve .15 has electrical connectiomwithxa thermostat' 16; mounted in .the adJa-l cent end wall. These partsare ofithe usual con- '-struction'.whereby thetvalve 15 is ,thermostatif lcally controlled so as to open :when a predetermined low .temperature is reached. in thev oven and to close when a predetermined high tempera- -v tu're is attained. From the foregoing itv will be seen that the burner 55 is constantly, supplied with gas soasto bumi andv provide a minimum jheat. Thisbvurner serves. as a pilot for lighting f the burners54 whenever they have been extingunned. u

On one end oi' the shaft 4I' which operates the .door 35 isjournaledacollar 11, as is. shown in Figures 6 and "I. This collar has -an arcuate slot 1| receiving e. pin `1a .festened iin me slim. an?

- arm'l extendsfrom the oollarwhen the shaft is rotated in a counter-clockwisedirection (Fig- Vures 1, 6- and '1)l and the pin will travel in the slot while the door n is being lowered. o Justfprlor to theend ofthe shaft rotation the pin engages the end of the slot and rotates the collar, whereby `the arm III is swung upwardly. vThis a nected by means'of a link 4| with an arf 32 fastened on the end of the shaft 53 of the front damper 52. When the door is closed the damper 52 is closed. Therefore, 1when the door reaches its full open position, the damper 521s opened by the mechanismV whichhas been described. 'Ihis provides ventilation so that the excess heat and. fumes are carried out back of the varch 48 into the manifold 44, as before referred to.

Y For operating theerear, damper 50, a lever 83 'is fastened on the projecting end of the shaft 5I. This lever is connected by a link with an arm 85 extending from the valve 15. When ,the valve is eon- I5 is closed, the arm 85 is moved downwardly. 75

whereby the lever 83 is swung to close the damper SII; but when' the valve is open the arm 85 is moved upwardly and the damper is thus swung open to set up ventilation in the baking oven.

From the foregoing it ,will be seen that a most emcient heating system -is provided. Cold air currents cannot enter the baking oven except when the door 35 is open or by back-flowing from the manifold 44, which is hardly possible. After the burners `have been set by adjusting the hand valves 6l and 69, the operation of the burners is entirely` automatic. When the temperature drops to a predetermined degree, the thermostat 16 causes the operation of the valve 15, and immediately a'maximum of"gas is supplied to the burners 54, thru the pipe'l. the damper 50 is opened and ventilation is established by way of the flue 41 and arch 46 to the manifold 44. This not only provides thel neces.

sary heat, but properly-ventilates the oven so as to carry olf excess heat. 'I'he flue 41 having its entrance at the bottom of the oven prevents cold a'ir entering the oven and also has a tendency to pull the excess heat from the top of the oven .downwardly without producing a chilling eifect.

Just as soon as the maximum heat is reached the thermostat closes the valve 15, whereby the gas burners 54 are extinguished and the damper 50 is closed. The supply is'reduced to a minimum being supplied by the pipe 68 and the burners remain lighted and serve to maintain the desired even heat in the oven.

It is pointed out that when the oven is rst put into use, the hand valve 69 is opened. The

gas from the main supply line 14 by-passes thel electric valve 15 and iiows thru the pipe '68, past the valve 69 and into the manifold 59. From the manifold, the gas enters any of the burners 54 which may have their individual hand valves 6l' open. It is here brought out that the valves 6I are either wide open or entirely closed, the viow of gas thereto being controlled by the valve 69. The pilot burner 55 is supplied by gas from the pipe 65 as has been described, and has been previously lighted normally by the nozzle 12.

Thus Whenever the valve 69 is opened, the burners 54 are supplied with gas and are ignited by the pilot 55. The Valve 69 is open only sufficiently far to supply a minimum amount of gas to the burners 54. When the temperature of the oven falls to the predetermined low point, the thermostat 1B operates the electric valve 15 to permit gas to enter the manifold 59 thru the pipe 61 and supply the burners 54 with a maximum amount of gas. Whenever the valve 15 closes, the burners 54 are not extinguished but burn on a minimum amount of gas. With this arrangement, the burners 54 either burn at a maximum or a minimum, there being no intermediate position. However, if desired, the hand valves 6| can be individually adjusted to intermediate positions altho it has been found that by controlling the supply of gas by the valve 69, betterY results are obtained. It is notedthat the pilot 55 is not connected with the manifold 59, being always manually controlled, while the burners 54 have theminimum gas supplied thereto manually controlled by the hand valve 69 and the maximum gas supplied thereto automatically controlled by the electric valve 15.

What I claim and desire to secure by Letters Patent, is:

1. A baking oven including, walls each formed At the same time'j burners.

of inner and outer frames, each frame comprising a plurality of angular. members, a sheet secured to each outer frame, a lining secured to each inner frame, means for securing the inner frames together, angular battens connecting the outer frames, and narrowV transverse straps spaced from-each other extending between the inner and outer frames whereby said frames are secured together, the space between the frames being filled with insulating material. I

2. A lbaking oven including, walls each formed of 'inner frames comprising a pluralityof angleI bars and outer frames also comprising a plurality of angle bars, said bars having their flat sides outward, a sheet secured to each outer frame, a lining fastened to each inner frame, the angle bars of the inner frames beingv bolted together, angular battens bolted to the outer frames, and narrow transverse straps spaced a considerable distance from each other extending between the inner and outer frames whereby said frames are secured together, the space bej tween the frames being filled with insulating a material. f

3. A baking'oven including, a baking chamber having a. front Ventilating arch and a rear ventilating arch, a burner for providing a minimum heat within the oven, a fuel supply line connected to said burner, a second burner for providing a maximum heat within the oven, a fuel supply line, connected with said second burner, a single automatic control valve connected in the supply line, a door at the front of the oven adjacent the front arch, a damper controlling the ventilation of the front arch actuated by the door, and a damper controlling the ventilation of the rear arch connected with the fuel control valve and actuated thereby.

4. A baking oven including, insulated walls,

burners in the bottom of the oven for supplying a maximum heat, a fuel supply line connected with said burners, a. thermostatically controlled valve connected in said line for controlling the fuel to said burners, a minimum heat burner contiguous vto the maximum burners, a fuel supply line having one end connected with the minimum heat burners, a minimum heat burner adjacent the maximum heat burners, a thermostatically controlled valve in the supply line for controlling the fuel supply to the maximum heat burners, means for by-passing a restricted amount of fuel around said valve to both the minimum burner and maximum burners to supply a reduced amount of fuel to the maximum burners and to constantly supply said minimum burner, an oyen ventilator directly connected to and actuated/ by said valve, I

whereby the ventilation is controlled in proportion to the .fuel supplied to maximum heat LOUIS D. HOULIS. 

